The present invention relates generally to semiconductor fabrication and more specifically to a method of improving the adhesion of photoresist after reworking.
During fabrication of semiconductor integrated circuit (IC) devices, it may become necessary to rework, or remove and reapply, metal photoresist. However, metal photoresist rework leads to yield loss due to the reapplied photoresist peeling inducing metal shorting. This is especially true for 0.18 xcexcm logic products.
U.S. Pat. No. 6,143,666 to Lin et al. describes a method for forming a via through a dielectric layer within a microelectronics fabrication. A silicon oxide dielectric layer is formed over a substrate and is then treated with an oxygen plasma to enhance adhesion to a photoresist layer formed over the oxygen plasma treated silicon oxide dielectric layer.
U.S. Pat. No. 6,143,670 to Cheng et al. describes a method for forming a composite dielectric layer with enhanced adhesion upon a substrate by treating with ion implantation methods.
U.S. Pat. No. 6,096,662 to Ngo et al. describes a method of manufacturing a semiconductor device with improved adhesion between the local interconnect etch stop layer and the thermal oxide in an isolation region.
U.S. Pat. No. 5,714,037 to Puntambekar et al. describes methods for improving adhesion between various materials utilized in the fabrication of integrated circuits. In one method, the surface of a silicon dioxide (oxide) layer is treated with a nitrogen plasma in a reactive ion etching process prior to depositing a silicon nitride film upon the treated oxide layer.
U.S. Pat. No. 4,330,569 to Gulett et al. describes a method of conditioning a nitride surface by treating it with ionized oxygen.
U.S. Pat. No. 6,153,512 to Chang et al. describes a process to improve adhesion of hydrogen silsesquioxane (HSQ) MD layer to underlying materials. A series of plasma treatments performed in a nitrogen containing ambient are used to improve the adhesion of the hydrogen silsesquioxane (HSQ) IMD layer.
U.S. Pat. No. 5,795,821 to Bacchetta et al. describes a method for improved adhesion between dielectric materials at their interface by interposing a thin oxide layer between a first and second dielectric layer.
Accordingly, it is an object of the present invention to provide a method of improving adhesion between an inorganic anti-reflective coating (ARC) layer and photoresist after a metal photoresist rework
Other objects will appear hereinafter.
It has now been discovered that the above and other objects of the present invention may be accomplished in the following manner. Specifically, a semiconductor structure having an upper exposed metal layer is provided. An ARC layer is formed over the upper exposed metal layer. The ARC layer having an upper surface. A first photoresist layer is formed upon the ARC layer. The first photoresist layer is removed by a rework process. The ARC layer upper surface is roughened to form a roughened ARC layer upper surface. A second photoresist layer is formed upon the roughened ARC layer upper surface whereby adhesion of the second photoresist layer to the ARC layer is improved.